The RO Group is delighted to announce that its flagship property in Milton Keynes, Silbury House, has achieved a 5 Star NABERS UK Energy for Offices Whole Building rating, recognising the building’s outstanding operational energy performance.
Silbury House is currently the only building in the UK to hold a 5 Star NABERS UK rating, and is the third highest-rated Whole Building certified in the country.
NABERS UK measures the actual energy use of office buildings, rather than their predicted performance at the design stage, providing independent verification of how efficiently a building is operating in practice.
The rating represents the latest milestone in RO’s extensive refurbishment of Silbury House, originally constructed in 1998. The project set out to transform the existing building into the most sustainable office building in Milton Keynes, significantly improving its energy efficiency while avoiding the embodied carbon associated with demolition and redevelopment.
The refurbishment has included the installation of 116 rooftop solar panels with a total capacity of 41 kWp, capable of generating up to 20% of the building’s energy demand. The building also benefits from an energy-efficient hybrid Variable Refrigerant Flow heating and cooling system with heat recovery technology, alongside LED lighting and advanced controls designed to reduce energy consumption. These measures have already helped Silbury House achieve an EPC A+ ( Net zero) rating.
Silbury House’s sustainability credentials extend beyond energy performance. The building has secured a 3 Star Fitwel certification for health and wellbeing, making it the only building in Milton Keynes to hold the accreditation. Further reinforcing its focus on building performance, it is also the only building in the region to achieve and maintain RESET Air Certification, with indoor air quality continuously monitored, and independently verified against globally recognised standards, to ensure a healthy, comfortable and productive indoor environment for occupiers.
Sustainability was also embedded in the materials and construction process. Existing materials were retained and repurposed wherever possible, including recovered raised access flooring, while carpet tiles contain 75% recycled content. No waste generated by the refurbishment was sent to landfill.
Ana Bajri, Group Head of Sustainability at the RO Group, said:
“Achieving a 5 Star NABERS UK Whole Building rating is a significant milestone for Silbury House and demonstrates what can be achieved through thoughtful investment in existing buildings.
“What is particularly important about NABERS is that it measures actual operational performance. This rating provides independent evidence that the work undertaken at Silbury House is delivering lower energy consumption and greater efficiency for our occupiers.
“We have shown that an existing building can be transformed to meet the standards expected of modern, high-quality office space. Being the only building in the UK currently holding a 5 Star NABERS UK whole building rating is a fantastic recognition. For us, this is not simply about achieving a certification; it is about using real performance data to create better buildings for occupiers and the environment.
Silbury House demonstrates that sustainability, occupier experience and commercial performance can go hand in hand. We hope it provides confidence to other building owners considering how they can improve the performance of their existing assets.’’
NABERS UK was launched in 2020 and is administered by the Chartered Institution of Building Services Engineers (CIBSE). Its Energy for Offices ratings assess the measured operational energy performance of existing office buildings, enabling owners and occupiers to understand, track and improve energy efficiency.
Silbury House provides Grade A office accommodation in central Milton Keynes, incorporating smart building technology, fitted office suites and upgraded amenities as part the RO Group’s comprehensive refurbishment of the property.
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